Tag Archive for Ethernet

| November 17, 2015
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Sun Setting on Cat 5e

Sun Setting on Cat 5eThe sun is setting on the Cat 5e cabling standard. The long-standing standard defined how most commercial spaces around the world were cabled for nearly 20 years. Starting in 2017 Cat 5e will be considered obsolete for new installations following a decision by the ISO/IEC cabling standards body.

recommendation for Category 6AIn a recent blog post at CommScope (COMM), the ISO cabling standards body JTC1/SC25 WG3 working group agreed to raise the minimum horizontal cabling requirement. The new standard is stated in ISO/IEC 11801-2. Office space requirements change from Class D (Category 5e) to Class E (Category 6). It includes a recommendation for Class EA (Category 6A). Cat 6A will enable a smooth migration to 2.5, 5, and ultimately 10 gigabits per second (Gbps). In the drafts of 11801-5 (data centers) and 11801-6 (distributed services), the minimum requirement is already Class EA cabling.

Ethernet and IP communications everywhere

The original ISO/IEC 11801 standard enabled the explosive growth and mass deployment of Ethernet and IP communications everywhere. In its first edition, the author says the standard defined Class D balanced cabling based on Category 5 copper components. This standard offered an upgrade path from 10 to 100 megabits per second (Mbps) up to 100 meters. At that time, some experts and industry observers argued that 100 Mbps (100BASE-T) to the desk was overkill for the typical office user.

handful of cablesToday, 100BASE-T technology is in a rapid market decline. 100BASE-T is being replaced with 1000BASE-T (1 Gbps) according to the article. 1000BASE-T is commonplace for desktop and laptop PCs. It also benefits a wide range of other devices such as phones, cameras, and wireless access points (WAPs).

The 11801 standard now includes more cabling classes that were introduced to enable support of up to 10 Gbps. The new classes include Class E (Category 6), Class F (Category 7). Even more recently, Class EA (Category 6A) and Class FA (Category 7A).

Technology trends

According to the CommScope blog, a number of technology trends made ISO choose to upgrade the minimum recommendation for horizontal cabling in offices. Some of the trends recognized by the committee that are driving the adoption of speeds beyond one Captain Ethernetgigabit on the horizontal cabling include:

The rapid growth of BYOD is driving infrastructure upgrades to accommodate IEEE 802.11ac. As I have covered before, new IEEE specifications are being developed to accommodate 802.11ac wireless. 2.5GBASE-T is targeted at installed Class D cabling and 5GBASE-T is targeted at installed Class E cabling. It is expected that a sizable percentage of the installed base will be able to support the faster speeds, however, some installed Class D and Class E systems may require some mitigation steps.

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Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.

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| April 16, 2015
Comments Off on Wi-Fi Charges Up Ethernet

Wi-Fi Charges Up Ethernet

Wi-Fi Charges Up EthernetInformation Technology prognosticators Gartner (IT) predicts that 40% of enterprises will use Wi-Fi as the default connection for mobile and non-mobile devices by 2018 according to Fred Donovan at FierceMobileIT. The prediction says that typically fixed location devices like; desktops, desk phones, projectors, and conference rooms will use Wi-Fi as their primary connection replacing Ethernet.

Wi-FI logoGartner says Wi-Fi is facilitating BYOD. The enterprise Wi-Fi network now allows workers to choose any device and move anywhere in the workplace. Gartner argues that the introduction of security measures like 802.1X augmented with Advanced Encryption Standard (AES) encryption has lessened IT’s worry about security breaches involving the Wi-Fi infrastructure. Ken Dulaney, V.P. and distinguished analyst at Gartner said;

Ethernet cabling has been the mainstay of business workspace connectivity since the beginning of networking. However, as smartphones, laptops, tablets, and other consumer devices have multiplied, the consumer space has largely converted to a wireless-first world

Facilitating BYOD

As the first connection to the enterprise infrastructure, Wi-Fi brings workers the ability to choose any device and move anywhere without worry. VP Dulaney continued;

WI-FI certifiedAs bring your own device (BYOD) has increased in many organizations, the collision of the business and consumer worlds has changed workers’ demands

Furthermore, cabling systems or even peer-to-peer (P2P) wireless solutions using technologies that offer cable replacement have had to deal with a variety of connectors challenges, such as USB and micro-USB, as video systems move beyond Video Graphics Array (VGA). The market research firm also argues that MACD costs will decrease.

MACD costsAdditions, moves, and changes are costly inconveniences that waste time for enterprise IT organizations. A move can sometimes involve cabling changes that can cost as much as $1,000 … With Wi-Fi printers, desktops, and other devices, all that is required is a cable to the power source, leaving workers free to move themselves making reconfigurations of offices easier.

Because of the many benefits of Wi-FI, Gartner VP Dulaney predicts firms are going to change how they connect;

we expect many organizations to shift to a wireless-by-default and a wired-by-exception model.

New Ethernet specifications

In order to deal with the new wireless-by-default reality, changes are needed on the wired network.  at FierceCIO reports that the vendor community is working to address the Wi-Fi first world. Unfortunately, there are two industry groups pushing their own new Ethernet specifications. Mr. Mah says that new Ethernet standards are needed to work with Wave 2 of 802.11ac wireless access points (AP) with a theoretical maximum throughput of up to 3.5Gbps.

NCaptain Ethernetew standards are needed because the existing Gigabit Ethernet is a bottleneck and current alternatives are not attractive. First, link-aggregating two Gigabit Ethernet connections for each Wi-Fi AP would need additional cabling and more expensive managed switches to support it. Using 10GbE would be overkill. Upgrading to 10GbE is a significant investment that includes new Category 6a or Category 7 cables, more power, and more cabling.

One faction, the MGBase-T Alliance, was formed in June 2014 and includes; Avaya, Aruba Networks (ARUN), and Brocade (BRCD) as well as component vendors Broadcom (BRCM) and Freescale Semiconductor. The other group known as the NBase-T Alliance was formed in October 2014. This faction consists of Cisco (CSCO), Intel, Xilinx (XLNX), Freescale, and Aquantia, a company that’s already making 2.5G/5G components.

Little agreement on standards

At the moment, the only agreement between the two factions is that 2.5Gbps and 5Gbps speeds are needed. The IEEE 802 LAN/MAN Standards Committee has set up the P802.3bz 2.5/5GBase-T Task Force to address this issue. The 2015 Q1 CommScope Standards Advisor reports that the 802.3bz Ethernet cablescommittee has decided so far that:

  • 2.5 GBase-T option will run on Cat 5e (Class D) 4 pair UTP up to 100M, and
  • 5 GBase-T option will run on Cat 6 (Class E) 4 pair UTP up to 100M.
  • There is no release date yet

The concern, however, is that vendors could jump the gun by shipping pre-standard products ahead of standards rectification, complicating matters and slowing down the development of the pertinent standards.

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Remember 802.11n? Pre-standard products? Given that there is no guarantee that systems built with components from the two groups will work together. Don’t jump the gun – waiting for the standard to solidify before buying into new 2.5G/5G Ethernet networking hardware.

For now, Dell’Oro Group analyst Alan Weckel told FierceCIO is that enterprises will probably be able to buy 2.5G/5G equipment starting in Q2 of 2015. 

 

Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.

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| April 9, 2015
Comments Off on 802.3bt More Power to the People’s Devices

802.3bt More Power to the People’s Devices

802.3bt More Power to the People's DevicesPower over Ethernet (PoE) powers more than one million end devices today. To continue PoE’s success, the IEEE is answering the market’s demands for more power by developing 802.3bt the third generation of PoE.

The first generation of PoE (2003), 802.3af delivered 12.95 Watts. The second generation, 802.3at (2009) provides 25.5 Watts to the equipment. The new version of PoE will address the need for higher-power PoE. The IEEE has proposed a new standard, 802.3bt, which promises to double the power output of the current 802.3at standard. The new 802.3bt standard, scheduled to be released in 2017, will also adjust PoE to work with 10Gbase-T.

IEEE logoCabling Installation & Maintenance Magazine provides an excellent overview of the new standard. They report that the IEEE 802 LAN/MAN Standards Committee which develops and maintains networking standards like Ethernet, VLANs, and Wireless LAN, is developing the new standard. The DTE Power via MDI over 4-Pair Task Force is working to specify a set of next-generation PoE specifications, and the levels of power likely to be delivered ultimately via the 802.3bt standard will still work on twisted-pair cable, possibly as a four-pair PoE specification which could improve energy efficiency and offer greater power.

New POE Applications

IndustryApplicationTypical Power Consumption
HealthcareNurse call system30-50W
RetailPoint of sale system30-60W
BankingIP Turrets45W
Building ManagementVariable air volume controllers, Access controllers40-50W
Enterprise ITThin clients, Virtual desktop terminals50W
HospitalityPOE switches45-60W
Premise SecurityPTZ cameras30-60W
IndustrialBrushless drives, Motor control>30W
VariousDigital signage>30W
VariousMultichannel wireless access points>30W
via CommScope

The new PoE standard will support 10GBase-T. The 10GBase-T standard uses all 4 pairs to send data. These facts will force the IEEE 802.3bt committee to figure out how to keep the power from interfering with the data on the same wires to supply a minimum of 49 watts at the powered device. One of the key parameters the article mentions is to limit pair-to-pair current imbalance.

POE logoOther goals for the 802.3bt standard are: to be backward-compatible with “af” and “at.” and increased energy efficiency. According to the article, a global move to 4-pair POE systems would create potential energy savings of 60.8 million kilowatt-hours which would prevent greenhouse gasses from 66 million pounds of coal saved annually.

Paul Vanderlaan, technical manager of cable maker Berk-Tek – Nexans’ advanced design and applications lab and other cabling-industry technical experts believe that 802.3bt’s support of 10GBase-T means that the minimum twisted-pair cabling system requirement will increase.  In order to support 10GBase-T, it seems likely that a Category 6A system will be the recommendation. The author notes that the IEEE does not address cabling performance, that is the focus of groups like the TIA or ISO/IEC.

The transition to the new PoE standard will not be simple. CommScope published a white paper where they explain:

Category 6A cabling… Category 5e cabling only provides the minimum level of performance required. Therefore, it is recommended to use Category 6 or Category 6A cabling-preferably solutions … 

Berk-Tek’s Vanderlaan explained why Category 6A cabling is the preferred system. He summarizes the electrical-engineering calculations;

As a general rule, increased copper content, or larger gauge size, will aid in power delivery … when you migrate … you should see larger gauge sizes and more copper content.

system performance characteristicsUnder the new standard users will have to pay attention to new cabling-system performance characteristics like DC resistance unbalance and pair-to-pair resistance imbalance.  The higher wattage’s up to 1 full amp (1,00 milliamps) will present challenges to performance requirements. Mr. Vanderlaan told Cabling Installation & Maintenance Magazine:

For users, cable selection will be based not just on the speed that can be supported, but rather on speed as well as power delivery. What you simply plug in today, you may want to also power in the future.

A new challenge cable plant owners will have to consider is heat. CommScope explains that heat generated within bundles of cables supporting IEEE 802.3bt could rise enough to effect performance.

ambient temperature… the temperature of the cabling will rise due to heat generation in the copper conductors  … the temperature of the cable bundle higher than the ambient temperature of the surrounding environment … The IEEE 802.3bt four-pair PoE standard is expected to assume a maximum temperature rise of 10 degrees Celsius (50 degrees F) when all four pairs are energized … the ambient temperature should not exceed 50 degrees Celsius (122 degrees F) … CommScope recommends Category 6A cabling for four-pair PoE applications. Because increased thermal loading can also increase insertion loss, the maximum cable length should be de-rated for higher temperatures, per ANSI/TIA-568-C.2.

Several vendors have already released pre-standard device-powering systems to meet users’ current needs.

As in the pre-PoE standard days, Cisco (CSCO) has marketed proprietary PoE systems since 2011. Cisco’s Universal Power Over Ethernet (UPOE) technology, which delivers 60 watts of power to devices powered by the Catalyst 4500E; some of those devices include Cisco IP phones, personal telepresence systems, compact switches and wireless access points.

Also, the non-standard Power Over HDBase-T (POH) was introduced by the HDBase-T Alliance a trade group that promotes and standardizes HDBase-T technology for whole-home distribution of uncompressed high-definition (HD) multimedia content. This system delivers up to 100 watts of power to TVs and other devices over distances up to 100 meters/320 feet via one Category 5e or 6 cable with standard RJ45 connectors.

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The new standard is a welcome addition to the toolkit. Cost savings is one of the appeals to PoE. On many projects, PoE low voltage contractors can do the work rather than electrical contractors. If the new system pushes the maximum rate to 75W at the devices as some predict, with there be a backlash from the EC’s and authorities having jurisdiction? Time will tell.

In the meantime, the article says owners and managers should check their current infrastructure with eyes toward how the next generation of devices might be powered via more-capable PoE technology.

Of course, it is always a good idea to pull out your acceptance documentation to understand the installed base of the cable and the likelihood that the cable has the electrical performance characteristics required to support the next generation of PoE.

Related articles

 

Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.

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| April 23, 2014
Comments Off on No More POTS!

No More POTS!

No More POTS!A.G. Bell‘s question to Watson over a century ago may be relevant again. Tom Nolle at No Jitter explains how that can happen if the FCC expedites the transition to VoIP. Mr. Nolle, the founder of CIMI Corporation does not think that the basic quality of voice service is at risk. He does believe but there are some truly profound consequences to a decision to abandon TDM voice. He believes it will happen, it’s smart to think about the end of POTS — as relates to both opportunities and risks.

70% of business voice is still TDMTelecommunications has long been more than analog voice and copper loops. The author points out that regulations have stayed in the “TDM” Dark Ages. Operators like AT&T (T) have demanded the FCC modernize things. To deal with these issues, the FCC bundled its transitions (TDM-to-VoIP, fixed to mobile, copper to fiber) into a single Technology Transition Policy Task Force. The recommendations from that activity will hopefully launch experiments in promoting change while controlling the risk of unfavorable impacts. The recommendations of the TTPTF (quite the acronym!) are posted online (PDF) and he says it’s a clarion call for change. So instead of talking about the process, let’s look at the impact.

Who still uses TDM

Mr. Nolle the CIMI principal consultant estimates, that 40% of US households still have TDM voice. Businesses have a higher TDM commitment. The article says that nearly 70% of business voice is still TDM. Suppose we saw TDM voice go away completely; what would happen?

Transition access lines and trunks to EthernetFirst, little besides voice that requires TDM services and trunks. Which he says means we would see all access lines and trunks transition to packet–almost certainly to Ethernet. The author says this could increase the number of Ethernet business connections by about 28%. it would also likely increase the access bandwidth commitments by branch offices and SMBs (using DSL, fiber, cable, etc.) by over 50%. Metro and access vendors would benefit from this almost immediately because it’s likely that operators would start to promote Ethernet access and IP voice more strongly as soon as the “experiments” showed signs of success.

Operators already like the notion of an “access-first” strategy where they supply a fat pipe to a customer and then build ad hoc services over it. Ethernet or packet access encourages that, so giving that to everyone would drive operators quickly to look for rapid service deployment tools so that they don’t lose all the new access-generated opportunities to the over-the-top players (OTTs). The author believes that operator interest in software defined networks (SDN) and network functions virtualization (NFV) are linked to this very thing. After all it’s silly to talk about “improved service velocity” if you have to restring an access connection to upgrade service.

Impact on Internet policy

Net neutrailityThe second impact Mr. Nolle sees is on Internet policy. This voice transition raises the question of the difference between “packet” or “IP” and “the Internet”. You can do VoIP over any IP, including private networking. That’s done with a lot of IP voice today in fact. Operators could in theory augment their services to customers by building IP services that bypass the Internet, but that would pose issues in linking the services to current devices in the home or in businesses. OTTs would surely want to get involved in any new service opportunity, and all that raises the triple-threat question of QoS, settlement, and Net Neutrality.

There’s no barrier to QoS in “private” IP networks, but on the Internet, the Net Neutrality order last year said that you could offer QoS only if the subscriber pays for it. Most practical Internet QoS opportunities arise because an OTT like Netflix (NFLX) could gain by offering QoS to customers. They’d pay the ISPs and either embed the cost or perhaps eat it to improve their differentiation. But the FCC said “No!” Now the new FCC Chairman, Tom Wheeler, says “Perhaps”–at least he did in a speech to a university audience. If that were to become policy, it would likely drive QoS for Internet services, and that would drive settlement among ISPs and content players.

QoS stops where the ISP hands off the trafficSettlement has been a big issue for the Internet since the 1990s. Customers pay their own ISP, so if there’s no money flow from that ISP to others, QoS stops where the ISP hands off the traffic. That’s inhibited the value of the Internet for applications that need QoS, but it perhaps encouraged smaller players and startups who couldn’t pay like Google (GOOG) or Netflix could. Whether this small-player benefit is more for VCs who then have to raise less funding to get an OTT off the ground is an interesting question–but in any event, adding settlement and QoS to the Internet would almost certainly increase operator interest in providing service quality for a fee, which in turn would increase network investment, helping equipment vendors and carriers alike… In short, it would change the industry.

Mr. Nolle concludes that VoIP could be a back door to making the Internet a real network and not a service on top of carrier IP infrastructure. That could remake our experiences online, and the vendors’ fortunes in the marketplace. So watch the progress of this initiative; it could have huge impacts.

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ATT has already made its move to get rid of POTS lines in Michigan. ATT has bribed gotten politicians in Lansing to introduce Senate Bill 636. Michigan SB 636 would amend the Michigan Telecommunications Act (PDF) to let ATT and their fellow travelers eliminate POTS lines in Michigan.

Melissa Seifert, associate state director for government affairs for AARP Michigan says eliminating POTS lines in the Great Lakes State would impact many people. It would affect small-business owners who use fax machines and credit card verification systems, she said, as well as emergency services in parts of the state where cell phone access is unreliable. According to the Michigan Public Service Commission, roughly 3 million Michiganders subscribe to landline service. About 90 percent of households of folks ages 65 and older still use landlines for “lifelines.”

Related articles

 

Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.

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| December 17, 2013
Comments Off on Wiring Closet 3.0

Wiring Closet 3.0

Wiring Closet 3.0The lowly wiring closet at the edge of the network is evolving. You know the one’s that IT shares with the custodians or the women’s lav. The neglected place that connects all end-points into the enterprise network infrastructure. Throughout my career we have moved from 3Com SuperStack hubs to 10/100 SuperStack switches to 100/1000/10000 Cisco 2960’a fixed Ethernet devices. In this first edge era, the primary buying criteria was the price per port. Low price was the critical factor. These devices might have had a few network services but they only provided best-effort connectivity services with little to no operational control according to Nick Lippis in the Lippis Report 103: Wiring Closet Switches Gain Strategic IT Value Label.

Baystack stackCommoditized network gear created enterprise networks consisting of equipment from different vendors. Purchases throughout the wiring closets, distribution, and core were based mainly on cost. The article says that equipment from multiple vendors is the hallmark of Wiring Closet 1.0. Wiring Closet 1.0 made effective management difficult. Multiple management systems required that organizations keep a large staff with diverse skills to keep up network functionality.

Wiring Closet 2.0

Most organizations are now in the Wiring Closet 2.0 era. As competition drove margins on edge switches into the single digits, the author states that vendors began to add services to a new breed of device. The new features on 2.0 switches created new ways for the vendors to compete on different (rb- and more profitable) fronts beyond price per port. Mr. Lippis argues enterprise trends are forcing IT executives to check projects, programs, and priorities as they seek to drive down Total Cost of Ownership (TCO) while extracting added value from their enterprise network. Business executives expect their IT departments to meet continually growing demands without significant year-over-year network expenditures. (rb– the ever popular more with less argument) The article says the new realities include new mixed traffic patterns and increased desktop bandwidth requirements for new applications, communications, and data center strategies.

Goddard rocket scientistSwitch vendors recognized these trends. They responded by developing a new type of wiring closet switch. Second-generation switches added significant functionality. The vendors’ goal is to transform the commoditized network edge (rb- low profit) into a strategic IT asset (rb- high profit). The blog says these new switches enable a host of new applications for Wiring Closet 2.0.

  • Quality of Service: Wiring Closet 2.0 switches tag applications like IP telephony and Unified Communications at access to guarantee priority throughout an internal network and active monitoring
  • Power Over Ethernet (PoE): Second generation, wiring closets distribute power over Ethernet cables. POE enables new classes of devices to be powered from the Wiring Closet 2.0. These demands include WLAN access points, video surveillance, and IP phones. As well as specialty devices such as health care instrumentation, point of sale devices and soon even laptops.
  • Security: The network edge Is the first level of defense. Network Access Control (NAC) and application policing have increased in importance. They are needed to protect the integrity of the network, data privacy, and compliance. Wiring Closet 2.0 switches integrate security features and the support of security appliances bolstering defense-in-depth strategies.
  • Wireless Local Area Networking: WLAN integration, which includes access point, PoE, and controller support, increases WLAN coverage. Further common network management interfaces streamline operational support for both wired and wireless networks.
  • Unified Communication (UC): UC support via PoE to power IP phones and UC end-points plus unique UC configuration profiles to ensure reliable and stable UC operation.
  • Application Intelligence: Application intelligence or the categorizing of applications as they enter the wiring closet and either mark them with QoS or discard the application. This enables application policing at the network edge.
  • Layer 3: Full layer 3 forwarding enabling all the value associating with routing including segmentation and aggregation are now included in some wiring closet switches.
  • Total Cost of Ownership: The network edge and wiring closet switches in particular have a TCO breakdown of 20% capital spend and 80% operational spend according to Gartner (IT). Mew wiring closet switches are more expensive from a capital acquisition point of view. However, their operational cost is lower. Thus, the total dollar spend over a three-year period will also be lower while delivering increased value to the enterprise.

Wiring Closet 3.0

The IT industry is on the verge of a new era at the network edge. New technologies and requirements will disrupt Wiring Closet 2.0.

  • 10Gbps Ethernet: 10Gbps Ethernet is the future of networking. If the past is a guide to the future, then over time more and more 1 Gbps Ethernet ports will upgrade to 10 Gbps. This will place a strain on wiring closet packet processing performance while driving up 10Gbps port density requirements plus downstream distribution and core switch capabilities.
  • Software-defined networking (SDN): The holy grail of SDN is to separate the network control plane from the data plane. The model I carry in my head is wireless networks. There is a central controller that tells the WAP’s what to do and they do their job without any help from the central controller. This implies that the network devices can be dumber and cheaper.
  • Network Management: Consistent network management means leveraging the same supplier for the network edge, distribution, and core.
  • True Layer 3 Support: To support all the above-mentioned trends and unforeseen applications, wiring closet switches need to support full layer 3 forwarding.
  • Support of UC, Mobility, and Security: This basis of competition is one of the most important attributes to the new network edge. Wiring closet switches need to support both standard interfaces and services for UC, mobility, and security so that mixed vendor solutions may occur.
  • IPv6: If you have wiring closets full of perfectly good Layer 2 switches, there’s no reason to replace them just because you can’t manage them with IPv6. If they work today, they’ll work until they break, and you don’t need to worry about (or budget for) swapping them out any sooner.

IPv6

IPv6

Dan Campbell, President, Millennia Systems, Inc. suggested in a recent CircleID post that to manage the move to an IPv6 enabled Wiring Closet 3.0. Organizations should strive to use theIPv6 dual-stack migration strategy. This is where IPv6 is added to the existing systems so they can simultaneously function with both IP versions. Tunneling and translation techniques should be used when the dual-protocol configuration is not possible. The mantra of “dual stack where you can, tunnel where you must” is the order of the day.

He advises that starting today, don’t buy another box unless it supports dual-stack operation or offers a clear, well-defined upgrade plan. It doesn’t matter if the manufacturer is “up and to the right” in the latest Gartner (IT) report; anything you buy from now on that is IPv4-only is a waste of valuable resources.

Mr. Campbell tells network administrators that while LAN switches function mainly at layer 2. They forward Ethernet frames regardless of whether the packet inside is IPv4 or IPv6. There are some functions on a switch that works at layer 3 or higher. They include:

• Dynamic ARP Inspection (DAI).
• DHCP Snooping.
• Multicast Listener Discovery (MLD) Snooping (the IPv6 equivalent of IGMP Snooping).
• Quality of Service (QoS) marking for upstream Differentiated Services treatment.
• Access Lists (e.g., VLAN or regular ACLs).

He explains that these features need layer 3 or upper-layer information; Layer 3 is needed to inspect the packet header or payload inside the Ethernet frame. These features may not be things you are doing now, but you never know when you will. Security requirements and hardening guidelines are recommending things like DAI, DHCP Snooping, and ACLs at the access layer.

The more streaming video gets moved to IP networks, the more the need for multicast. MLD Snooping is necessary to improve performance. Finally, the continued convergence of voice, video, and other rich media and interactive applications to IP networks is furthering the need for QoS. It is always best to mark traffic as close to the edge as possible.

Related articles

Ralph Bach has been in IT long enough to know better and has blogged from his Bach Seat about IT, careers, and anything else that catches his attention since 2005. You can follow him on LinkedIn, Facebook, and Twitter. Email the Bach Seat here.

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